I want to fetch articles from a feed and display them in TextViews, and I have been told to use IntentService to fetch the feed from the Internet so the app doesn't freeze, but I don't really get how to use it, and searching Google doesn't give any good examples.
Could someone explain this please? This is my IntentService sofar:
Code:
private class FetchFeed extends IntentService {
public FetchFeed() {
super("Lifehacker Fetch Feed");
// TODO Auto-generated constructor stub
}
@Override
protected void onHandleIntent(Intent intent) {
List<Message> messages = null;
try{
BaseFeedParser parser = new BaseFeedParser();
messages = parser.parse();
List<String> titles = new ArrayList<String>(messages.size());
for (Message msg : messages){
titles.add(msg.getTitle());
}
} catch (Throwable t){
Log.e("AndroidNews",t.getMessage(),t);
}
}
}
I'm currently developing an app and from within the app I'd like to let the user select custom images to use.
Right now I use
Code:
public final int GOT_IMAGE =1;
private void getImage() {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
mUri = Uri.fromFile(new
File(Environment.getExternalStorageDirectory(),"temp_image" +
".jpg"));
intent.putExtra(android.provider.MediaStore.EXTRA_OUTPUT, mUri);
try {
intent.putExtra("return-data", true);
startActivityForResult(intent,GOT_IMAGE );
} catch (ActivityNotFoundException e) {
e.printStackTrace();
}
}
protected void onActivityResult(int requestCode, int resultCode,
Intent data) {
if (resultCode != RESULT_OK) {
customImgChk.setChecked(false);
return;
}
if (requestCode == GOT_IMAGE) {
Bitmap image = BitmapFactory.decodeFile(mUri.getPath());
if (image!=null)
{
image = WPUtil.resizeBitmap(image, WPUtil.IMAGE_SIZE_X,
WPUtil.IMAGE_SIZE_Y);
}
else
{
customImgChk.setChecked(false);
Toast.makeText(this.getApplicationContext(), "Failed to grab
image!", Toast.LENGTH_LONG).show();
}
}
}
This works great on a few devices but not all. I'd really like to come up with a universal way to perform this function but I have not found a way to do it yet.
I've thought about writing up my own image selector and cropper but I'd rather not re-invent the wheel.
Can anybody suggest a decent app/library that I can use to select and or crop photos from within my app?
ImageJ is great. It is a stand alone app but there are published apis for integrating into your own apps.
*its better than that, its open source and you can use the jar and just ignore the gui library
Might look into that
http://rsbweb.nih.gov/ij/
From something awesome
You are new to java development and want to get buttons working?
Maybe you are a Pro but want a reminder?
whatever you are this Guide is to help you to make buttons/check boxes...etc working and functional
Some people are distracted between guides over internet and want the easiest way to get their project working, me too
Steps :
1-Define the button :
Code:
Button btn1;
Checkbox chkbox1;
RadioButton radio1;
2- Intialize it :
Code:
btn1 = (Button) findViewById(R.id.btn1);
chkbox1= (Checkbox ) findViewById(R.id.chkbox1);
radio1= (RadioButton) findViewById(R.id.radio1);
3-Add the listener :
Button:
Code:
btn1.setOnClickListener(new OnClickListener() {
@SuppressWarnings("deprecation")
@Override
public void onClick(View arg0) {
//Write awesome code here
}
});
CheckBox :
Code:
chkbox1.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
if (start.isChecked()) {
//if the checkbox checked
} else {
//if not checked
}
}
});
}
radio button:
Code:
public void onRadioButtonClicked(View view) {
boolean checked = ((RadioButton) view).isChecked();
switch(view.getId()) {
case R.id.radio1:
if (checked){
}
else{
}
break;
}
}
or use it in a radio Group :
Code:
public void onRadioButtonClicked(View view) {
// Is the button now checked?
boolean checked = ((RadioButton) view).isChecked();
// Check which radio button was clicked
switch(view.getId()) {
case R.id.radio1:
if (checked)
//Write code
break;
case R.id.radio2:
if (checked)
//Write code
break;
}
}
Also insted of this you can use a onCheckedChanged for a radio button (Thanks for GalaxyInABox)
Code:
@Override
public void onCheckedChanged(RadioGroup radioGroup, int i) {
switch (radioGroup.getCheckedRadioButtonId()) {
//Code
}
}
____________________________________________________________________
____________________________________________________________________
Also you can implement a Onclicklistener for the whole class to save resources : (thanks for @Jonny )
after defining and initializing your objects add this :
Code:
OnClickListener click_listener = new OnClickListener() {
public void onClick(View view) {
int id = view.getId();
if (id == your_id) {
//do stuff for this object
} else if (id == your_id2) {
//do other stuff for diffrent object
} else if (id == your_id3) {
//and so on
}
}
};
To do list :
-add on touch listeners
-add on drag listeners
Note : you can add a click listener to almost any thing (Textview or imageView or even EditText) just using the same method of adding listener to button
also there is some other ways to add a listener but this is the fastest and less disturbing :good:
If this guide is useful, press thanks
@ OP
CheckBox and RadioButtons don't they provide a CheckedChangeListener ?
Sent from my GT-S5302 using Tapatalk 2
sak-venom1997 said:
@ OP
CheckBox and RadioButtons don't they provide a CheckedChangeListener ?
Click to expand...
Click to collapse
Yes, and now you can use
Code:
@Override
public void onCheckedChanged(RadioGroup radioGroup, int i) {
switch (radioGroup.getCheckedRadioButtonId()) {
//Code
}
}
to get the checked button. They are pretty much the same, but you can use view.getTag() easier in the first one.
And @mohamedrashad please show how to put the listener into a inner class. Many people don't know/use it, but it's that useful!
GalaxyInABox said:
Yes, and now you can use
Code:
@Override
public void onCheckedChanged(RadioGroup radioGroup, int i) {
switch (radioGroup.getCheckedRadioButtonId()) {
//Code
}
}
to get the checked button. They are pretty much the same, but you can use view.getTag() easier in the first one.
Click to expand...
Click to collapse
I meant that the op shuld edit this guide and use those instead of OnCickListeners
GalaxyInABox said:
And @mohamedrashad please show how to put the listener into a inner class. Many people don't know/use it, but it's that useful!
Click to expand...
Click to collapse
ya new with java8 it will be a nice usage scenario of lambadas
Sent from my GT-S5302 using Tapatalk 2
GalaxyInABox said:
Yes, and now you can use
Code:
@Override
public void onCheckedChanged(RadioGroup radioGroup, int i) {
switch (radioGroup.getCheckedRadioButtonId()) {
//Code
}
}
to get the checked button. They are pretty much the same, but you can use view.getTag() easier in the first one.
And @mohamedrashad please show how to put the listener into a inner class. Many people don't know/use it, but it's that useful!
Click to expand...
Click to collapse
sak-venom1997 said:
@ OP
CheckBox and RadioButtons don't they provide a CheckedChangeListener ?
Sent from my GT-S5302 using Tapatalk 2
Click to expand...
Click to collapse
ok, i will add this
You can also add onClick property in XML and then handle it in a code.
Awesome tutorial! Thank you very much!
Please, you could share more related knowledge. It's really useful!
Also, an activity can be a listener. In this case:
MyActivity implements onClickListener {
btn1.setOnClickListener(this);
public void onClick (View v) {
//your code
}
}
For this kind of stuff, using some well known libraries from well known Android dev is a must.
https://github.com/JakeWharton/butterknife
Very powerfull, super easy to use, error prone and without any performance impact.
rafalniski said:
You can also add onClick property in XML and then handle it in a code.
Click to expand...
Click to collapse
SKAm69 said:
Also, an activity can be a listener. In this case:
MyActivity implements onClickListener {
btn1.setOnClickListener(this);
public void onClick (View v) {
//your code
}
}
Click to expand...
Click to collapse
will add them both, although I don't like this way
Mohamedrashad. Thanks a lot.
Sent from my P880 using Tapatalk
If you have multiple clickable objects then it's best to use just 1 onClickListener for all of them and use a switch on their ID's. This reduces resource usage as you only have 1 listener, not 5, 10 or however many you would have otherwise. It's not essential for this but it is a best practice if you want to streamline your code.
Mobile right now so I can't chuck up an example until tomorrow evening or so.
You dude had a great thread. Its helping me. Bravoo !!
Sent from my GT-I8190 using XDA Premium 4 mobile app
As @Jonny already pointed out: Use your class as a listener instead of creating a new (anonymous) inner class! Say you have a ListView, instead of doing this:
Code:
class MyFragment extends Fragment {
private void someMethod() {
((ListView) getView().findViewById(R.id.someListView)).setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
//Code...
}
});
}
}
you can do this:
Code:
class MyFragment extends ListFragment implements AdapterView.OnItemClickListener, View.OnClickListener {
private void someMethod() {
((ListView) getView().findViewById(R.id.someListView)).setOnItemClickListener(this);
}
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
//Code...
}
}
This may look stupid, but when you have many listeners, you can un-clutter it. In my opinion this is the best way. You can also add "this" class as listener for as many ui elements as you want(because all of them extend view, you can use one OnClickListener), then you only need to have a switch statement to distinguish between the views. And voila, you prevented cluttering the code with boilerplate stuff.
Example using code in an app I'm making - app for my school.
Code:
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// Some code here for view/layouts etc
websitebutton = (Button) view.findViewById(R.id.website_btn);
facebookbutton = (Button) view.findViewById(R.id.facebook_btn);
twitterbutton = (Button) view.findViewById(R.id.twitter_btn);
websitebutton.setOnClickListener(handler);
facebookbutton.setOnClickListener(handler);
twitterbutton.setOnClickListener(handler);
return view;
}
OnClickListener handler = new OnClickListener() {
public void onClick(View view) {
switch (view.getId()) {
case R.id.website_btn :
Uri website = Uri.parse("http://wirralgrammarboys.com/");
Intent websiteintent = new Intent(Intent.ACTION_VIEW, website);
startActivity(websiteintent);
break;
case R.id.facebook_btn :
Uri facebook = Uri.parse("https://www.facebook.com/WirralGSB");
Intent facebookintent = new Intent(Intent.ACTION_VIEW, facebook);
startActivity(facebookintent);
break;
case R.id.twitter_btn :
Uri twitter = Uri.parse("https://twitter.com/WGSB");
Intent twitterintent = new Intent(Intent.ACTION_VIEW, twitter);
startActivity(twitterintent);
break;
}
}
};
Jonny said:
Example using code in an app I'm making.
Code:
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// Some code here for view/layouts etc
websitebutton = (Button) view.findViewById(R.id.website_btn);
facebookbutton = (Button) view.findViewById(R.id.facebook_btn);
twitterbutton = (Button) view.findViewById(R.id.twitter_btn);
websitebutton.setOnClickListener(handler);
facebookbutton.setOnClickListener(handler);
twitterbutton.setOnClickListener(handler);
return view;
}
OnClickListener handler = new OnClickListener() {
public void onClick(View view) {
int id = view.getId();
if (id == R.id.website_btn) {
Uri website = Uri.parse("http://wirralgrammarboys.com/");
Intent websiteintent = new Intent(Intent.ACTION_VIEW, website);
startActivity(websiteintent);
} else if (id == R.id.facebook_btn) {
Uri facebook = Uri.parse("https://www.facebook.com/WirralGSB");
Intent facebookintent = new Intent(Intent.ACTION_VIEW, facebook);
startActivity(facebookintent);
} else if (id == R.id.twitter_btn) {
Uri twitter = Uri.parse("https://twitter.com/WGSB");
Intent twitterintent = new Intent(Intent.ACTION_VIEW, twitter);
startActivity(twitterintent);
}
}
};
Click to expand...
Click to collapse
i'm adding this to OP if you don't mind jonny
mohamedrashad said:
i'm adding this to OP if you don't mind jonny
Click to expand...
Click to collapse
That's fine - if I didn't want people to use/adapt/learn from the code then I wouldn't put it up, use it as you want :good:
Sent from my HTC One using Tapatalk
Keep it up
Great tutorials, keep em coming!
Hey what about starting a new activity with onClickListiner
Sent from my M3S_D7 using XDA Free mobile app
---------- Post added at 03:57 PM ---------- Previous post was at 03:49 PM ----------
Hey and do u mind sending a source codes.zip file
Sent from my M3S_D7 using XDA Free mobile app
Rebound.co said:
Hey what about starting a new activity with onClickListiner
Sent from my M3S_D7 using XDA Free mobile app
---------- Post added at 03:57 PM ---------- Previous post was at 03:49 PM ----------
Hey and do u mind sending a source codes.zip file
Sent from my M3S_D7 using XDA Free mobile app
Click to expand...
Click to collapse
in the onClick method just have this code:
Code:
startActivity(new Intent(this, YourActivity.class));
Hello,
I was wondering if anyone knows how to intercept all the traffic generated by the phone by using the VpnService class
from Android ?
So far I managed to create a virtual tunnel interface by using VpnService. However this interface intercepts only the traffic that
is directed to it( e.g. ping or telnet on the IP address of the tunnel interface ) and afterwards it redirects that traffic towards a server
( in my case, I considered, for simplicity, the server to be the loopback interface ). The rest of the traffic is not intercepted by the tunnel
interface.
If anyone could give me a hint or a code snippet on how to intercept all the traffic, I'd appreciate it very much.
Thank you !
Code:
public class VPNService extends VpnService {
private Thread mThread;
private ParcelFileDescriptor mInterface;
private FileInputStream in;
private FileOutputStream out;
private DatagramChannel tunnel;
//private SocketChannel tunnel;
private String TAG = "VPNService";
//a. Configure a builder for the interface.
Builder builder = new Builder();
// Services interface
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
// Start a new session by creating a new thread.
mThread = new Thread(new Runnable() {
@Override
public void run() {
try {
//a. Configure the TUN and get the interface.
mInterface = builder.setSession("VPNService")
.addAddress("192.168.0.1", 24)
.addRoute("0.0.0.0", 0).establish();
//b. Packets to be sent are queued in this input stream.
in = new FileInputStream(
mInterface.getFileDescriptor());
//b. Packets received need to be written to this output stream.
out = new FileOutputStream(
mInterface.getFileDescriptor());
//c. The UDP channel can be used to pass/get ip package to/from server
tunnel = DatagramChannel.open();
//tunnel = SocketChannel.open();
// Connect to the server, localhost is used for demonstration only.
tunnel.configureBlocking(false);
tunnel.connect(new InetSocketAddress("127.0.0.1", 8087));
//d. Protect this socket, so package send by it will not be feedback to the vpn service.
protect(tunnel.socket());
ByteBuffer packet = ByteBuffer.allocate(32767);
//e. Use a loop to pass packets.
while (true) {
int length = in.read(packet.array());
//Log.i(TAG,packet.array().toString());
if (length > 0){
packet.limit(length);
tunnel.write(packet);
packet.clear();
}
Thread.sleep(100);
}
} catch (Exception e) {
// Catch any exception
e.printStackTrace();
try {
in.close();
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
try {
out.close();
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
} finally {
try {
if (mInterface != null) {
mInterface.close();
mInterface = null;
}
} catch (Exception e) {
e.printStackTrace();
}
try {
tunnel.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}, "MyVpnRunnable");
//start the service
mThread.start();
return START_STICKY;
}
@Override
public void onDestroy() {
// TODO Auto-generated method stub
if (mThread != null) {
mThread.interrupt();
}
super.onDestroy();
}
}
Did you take a look at ToyVpn example from SDK?
I believe it's possible to tune it up to work with OpenVPN server.
Hi,
I'm trying to call setLength function of a RandomAccessFile object with a size of 262144000l (250 MB),
this call freezing my app for 10-15 seconds even when i'm trying to put the code on a new thread.
i think that this take that long time because android fills the file with zeros.
Why is this takes so long? can i force it not to fill the file with zeros?
My code:
Code:
Thread thread = new Thread(new Runnable(){
@Override
public void run()
{
try {
RandomAccessFile raf = new RandomAccessFile(new File("/storage/extSdCard/hey.aa"), "rw");
raf.setLength(262144000l);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}});
thread.start();
Thanks.
nirhal said:
Hi,
I'm trying to call setLength function of a RandomAccessFile object with a size of 262144000l (250 MB),
this call freezing my app for 10-15 seconds even when i'm trying to put the code on a new thread.
i think that this take that long time because android fills the file with zeros.
Why is this takes so long? can i force it not to fill the file with zeros?
My code:
Code:
Thread thread = new Thread(new Runnable(){
@Override
public void run()
{
try {
RandomAccessFile raf = new RandomAccessFile(new File("/storage/extSdCard/hey.aa"), "rw");
raf.setLength(262144000l);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}});
thread.start();
Thanks.
Click to expand...
Click to collapse
Looks like that thread is running on the UI thread and blocking it. You should use a new AsyncTask and put your code in the doInBackground method.